Stack corrupted with @autoreleasepool (ARC, compiled with llvm 3.0, Fastest, Smallest [-Os])

A small program which loads image and logs its size. It is compiled with ARC support, llvm 3.0. I run it on iPod 4.2 and get some funny numbers... The program is compiled in "Release" mode with "-Os" (default optimization for "Release" in xcode). This whole thing does NOT happen in Simulator. It looks to me that @autoreleasepool in combination with a loop corrupts stack... Note, that I had to isolate the problem for this post with this simple example.

--------->

int main(int argc, char *argv[])
{        
    @autoreleasepool
    {
        return UIApplicationMain(argc, argv, nil,
                                 @"AppDelegate");
    }    
}

@interface AppDelegate : UIWindow <UIApplicationDelegate>
@end

@implementation AppDelegate

-(void)loadImageAndLogValues
{
        // image from bundle 256x26
    UIImage *image = [UIImage imageNamed:@"Image.png"];

    for (int i = 0; i < 1; i++)
    {
      NSLog(@"size=%@", NSStringFromCGSize(image.size));
      NSLog(@"w=%f", image.size.width);
      NSLog(@"h=%f", image.size.height);
      NSLog(@"------------------------");
    }
}

-(BOOL)application:(UIApplication*)application
didFinishLaunchingWithOptions:(NSDictionary*)launchOptions
{
    self.frame = [UIScreen mainScreen].bounds;
    self.backgroundColor = [UIColor blueColor];
    [self makeKeyAndVisible];

    [self loadImageAndLogValues];

    UIGestureRecognizer *tap = [[UITapGestureRecognizer alloc]
        initWithTarget:self 
                action:@selector(loadImageAndLogValues)];
    [self addGestureRecognizer:tap];

    return YES;
}

@end

<------------------

And this is the output after I tap the screen once ("h" is WRONG when logged after tapping! The height of the image is 26...):

2011-10-21 01:54:48.677 Tmp[2522:307] size={256, 26}
2011-10-21 01:54:48.696 Tmp[2522:307] w=256.000000
2011-10-21 01:54:48.705 Tmp[2522:307] h=26.000000
2011-10-21 01:54:48.715 Tmp[2522:307] ------------------------
2011-10-21 01:54:50.576 Tmp[2522:307] size={256, 26}
2011-10-21 01:54:50.582 Tmp[2522:307] w=256.000000
2011-10-21 01:54:50.589 Tmp[2522:307] h=256.000000
2011-10-21 01:54:50.595 Tmp[2522:307] ------------------------

Now, I remove @autoreleasepool from main():

int main(int argc, char *argv[])
{        
        //@autoreleasepool
        //{
        return UIApplicationMain(argc, argv, nil,
                                 @"AppDelegate");
        //}    
}

Run the program and tap. Still wrong value for "h", but when calling "loadImageAndLogValues" directly from "application:didFinishLaunchingWithOptions:"...

2011-10-21 02:02:08.222 Tmp[2544:307] size={256, 26}
2011-10-21 02:02:08.240 Tmp[2544:307] w=256.000000
2011-10-21 02:02:08.250 Tmp[2544:307] h=256.000000
2011-10-21 02:02:08.259 Tmp[2544:307] ------------------------
2011-10-21 02:04:59.097 Tmp[2544:307] size={256, 26}
2011-10-21 02:04:59.103 Tmp[2544:307] w=256.000000
2011-10-21 02:04:59.109 Tmp[2544:307] h=26.000000
2011-10-21 02:04:59.115 Tmp[2544:307] ------------------------

So?... ARC + llvm 3.0 + -Os + @autoreleasepool + for(;;) + image.size.width/height is not working for me :) Please help! Thank you!

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